Paul McCartney is said to be distraught over further reports that his estranged wife, Heather Mills, modeled for two additional sex manuals during the 1980s.

Mills, who has acknowledged posing for one sex book (which she insisted was an educational lovemaking guide), may have taken her instructional duties to a greater level than originally thought. New pictures are circulating from one guide entitled "Sexual Secrets" depicting Mills being spanked, simulating sexual acts and taking part in bondage.

In one shot, Heather is seen exposing herself, while another photo shows the model draped over a male co-star's knee while he spanks her.

"Sexual Secrets" was published by New York firm Arlington who sold publications worldwide via an erotic book club. The graphic book describes itself as a photo "journey through exotic love acts." It does not contain any words.

The Sun, a British newspaper, also claims that Mills was featured in a top-shelf, adult French magazine. Rumors that Mills was formerly a high-priced call girl have also surfaced of late. The tabloid seems hell-bent on ruining the former model, but nonetheless, a friend of McCartney's reports that Sir Paul is taking the revelations hard.

"This will be yet another bombshell for him. Heather always insisted that her modelling past just included a sex guide," the source said. "Paul's since been made aware of how pornographic some pictures are. He has always thought the press were exaggerating her colurful past, but now he just isn't sure.

McCartney and his wife of four years are still on speaking terms, as they have to care for their two-year-old daughter, Beatrice. McCartney has been splitting time between his homes in London and East Sussex, England, since the couple's May 17 separation. Mills, 38, reportedly visited him this week, but conversations between the Beatle legend and his second wife have understandably turned icy. Mills has said she plans to sue the publications dragging her name through the mud once her divorce is settled.

She'll certainly be able to afford the lawyers. Gold digger.